Braking attachment



Juy RG, H923. TAGLS@ v J. l.. DEVON BRAKING ATTACHMENT Filed Aug. 15 1921 2 Sheets-Sheet l www@ 'A July l0; 1923.

, J. L. -DEVON BRAKING ATTACHMENT 2 Sheets-Sheet 2 Filed Aug. 15 1921 Patented duly ld, i923.

rvs.

JOSEPH L. BEVN, OF ATLANTA, GEORGL.

Bnerrrne arrastrar/rieur.

application sied august 5.5, 1921. semi no. 492,304.

To allfwtome't muy cof/wem.' j

Be it known that I, Josnrnr L. DEVON, residing at Atlanta, in the county of Fulton, State of `Georgia, and a citizen of the United States, have inventedcertain new and useful Improvements in Braking Attachments, of which the following is a specification.

The' object of my invention is to providey a novel braking attachment adapted more particularly for use with pumps installed on fire-engines, but which may be advantageously used in connection with any rotating shaft, and which is simple and compact in construction and organization, easy to install, and reliable in operation.

The accompanying drawing shows one form of embodiment of my invention ca` pable-of carrying out the underlying principles thereof, the attachment being shown in connection with a pump, of the rotary gear type, used on lire-engines. Like referenceecharacters denote corresponding parts throughout the severalviews.` Briefly described:

Figure l is la top plan view of a rotary gear pump, mounted on the frame or chassis of a fire-engine automobile or vother vehicle;

Figure 2 is a view in end elevation, a portion of the pump being broken awayv and one of the membersl of the chassis being shown in section;

Figure 8 is a fragmentary detail view, partly in section and partly in elevation, of part of the braking mechanism; v

Figure 4 is a fragmentary view in elevation of the pump with the side removed to show the gears; y Figure 5 is a fragmentary view, in sec tion, on the line 5 5 of Fig. 2, the brakeband and operating mechanism therefore being removed; and

Figure 6 is a detail view of the brakeband rocker.

ln the drawings, it willbe understood that the pump is not shown in detail, only i such parts thereof being shownas are necessary to an understanding of the applica-` tion of my invention'thereto.

Referring, now, in detail, to the drawlIlUSI designates the driving-gear of a rotarygear pump, such as is used on fire-engines, so called, of municipal fire-departments, and 2 the driven gear thereof, mounted, re-

spectively, on shafts 3 and 4l. It`will be noted, by reference to Fig. a, that, as ous tomarily constructed, there is a considerable amount of clearance between the meshing teeth, as shown at Afl TWhen drafting water, it is necessary, of course, to expel air from the suction pipe and suction charnber, and, sometimes, on a lift of ten feet or more, the pump fails; because, in order to discharge air from the suction faster than it will slip back into it from the discharge, the pump must be run at such speed that the gear-teeth break vContact at the point V, making an Opening for air to slip back into the suction `from the discharge chamber.

`When this form of pump is brand new, the packing 5 is tight enough on the shaft 2 to have the effect of a brake, and so, b preventing this vibration, holds the teeth constantly in contact. However, `when this packing becomes a little worn and smooth from wear, it does not grip the shaft so tightly, and then driven'gear 2 breaks contact with driyen-gear-l at the point V, and

air slips back into the suction-chamber from the discharge chamber.r My braking attachment prevents this, as will be apparent from a reading of the construction and ope 'a ion thereof.

To adapt the pump for use in connection with my braking attachment, the drivengear shaft 2 is extended back through the bearing retainer and dustecap (3, and is provided with an eXteriorly-projecting, reduced end 2a. 0n said end is mounted a drum 7, around which passes a brake-band S, the free ends 8', 8 of which are looped around pins 9, 9 passing through four ears l0 arranged in two pairs, one pair toward each end of a sleeve 'll rotatably mounted on a fulcrum pin 12 secured, at one end thereof, in. bearings 13 detachably secured to one of the cross-braces B of the side frame-members or channel bars C, C of the chassis of the lire-engine. rlhe sleeve ll and the two pairs of `ears l0 form part of a rocker or lever leihaving a web l5, the pin l2 constituting` the fulcrum of the lever. rlhe lever resembles, somewhat, a bell-crank lever of the conventional form, but is. a modified and peculiar form thereof. Instead of one shortl arm, as in the conventional bell-crank lever, my lever has two pairs of short arms (the ears l0), and the ears of each pair are connected by pins 9, 9. rlhe lower end of the Sli) lever is pivotally secured, as at 1G, to a socket member li', having a sei-eW-thrmuled socket, in Which may be screwed a pull-rod 18, having a screW-tl'ireaded end 19. The rod projects axially into a tubular member 20, having a pair oi lateral arms 2l proj ect ing through registering` slots 22, in one o the channel bars C and a Wear-platel, respectively. The Wear plate is disposed exteriorly oi the channel bar C (as shown in Fig) and suitably secured thereto.

fr eamlever 25 is tulcrunied on a pin 2G projecting` through the lever and through the arms 211,21, and hasy the curved cani 'face QTY-.hearing against the Wear plate Qil. l

The` tubular member 20 may Work in the cylindrical bore oit' a guide-member 2S.

`The guide-member 9.8 and the Wear plate 24 are secured to the channel bar C, preterahly by common means, such as screws 29.

One of the open ends ot the tubular inemberrQO is exteriorly threaded, and a screw closure-cai.) 3() is screwed on such threaded end, and is provided with a'central aperture, through which the pull-rod i8 projects.

Thefend ot the pull-rod i8 within 'the tubular member 2O is provided with a diskhead;I 3l, against Which one end ol" a coiled spring 32 bears, the other end olf said springbearing against the cap 30. The spring encircles the rod 18, as shown.

It will be noted that the attachment or braking-device describedis very simple and compact, and that, in operation, by pullingI down the lever 25, the brake-band 8 is tightened around the drum T, thereby bral:H ing the sha'i't et of the driven gear il. lt will be noted, Yt'urtherinore, that, in the operation of the lever Q5, it does not pull directly on the rod 18, but on the spring 32, thereby insuring uniform pressure on the brake-drum.

i/ienoei The lever 25 may be conveniently operated by a fireman standing on the ground beside the lire-engine, the lireinan pulling the lever to apply the brake until the pump is primed and the water is being discharged, The brake has then served its purpose, and should be tl'iereupon released to prevent wear on the brake-band and drum.

Having thus r'ully described my invention, the many advantages thereot will be apparent,especially to those skilled in the art to which it pertains. lt is obvious that many mechanical changes, especially iny detail, may beniade in the particular form oli device disclosed; but such changes do not necessarily depart trein the spirit of thein vention, or sacrilice any o'i'" its advantages, and all such as come `Within the terms of the appended elaiin 'lall Within the purview et the invention.

llllhat l claim to be new and desire to sccu-re by Letters-Patent of the United lStates is:

The Combiiiation with the chassis of a road vehicle, said chassis including a longitudinallyy extending channel-bar, of a rotat ingV shaft carried by said chassis, a brakeband forvsaid shaft, a pivetedA rocker to which the jiree ends el? said brake-band are secured, a pull-rod secured to said rocker, a tubular meinberloosely projecting through said channehbar and resiliently lconnected with said pulleroihya hand-lever pivotally secured to said tubular member and having` a czun t'ace hearing against said channel-bar, and asguide-member secured to said channelar and'having a cylindrical bore through Which said tubular member projects.

In testimony whereof l hereunto affix my signature.

JOSEH L. DEVN. 

